Jade in British ColumbiaInformation Circular 2012-3

For More Information

George J. SimandlIndustrial Mineral and Gemstone SpecialistGeological Survey BranchVictoria, B.C. Phone: 250-952-0413E-mail: george.simandl@gov.bc.ca

Selected ReferencesLeaming, S.F. 1978, Jade in Canada: Geological Survey of Canada, Paper 78-19, 59p.

Leaming, S.F. 1995, Jade in North America, in Roger Keverne, Editor; Jade: Annes Publishing Limited, London; p. 298-315.

Leedham, T.,1999: Working with jade: Newsletter, v.18, no.1, Gem and Mineral Federation of Canada, p. 8-9.

Scott, A.,1996, Jade a mystical mineral: Equinox, No.89, p. 64-69.

Simandl, G.J. and Gunning D.F. (2000): Dimension and ornamental stone in British Columbia; in Natural Stone in Canada, Roc Magnina, p. 47-51.

Simandl, G.J. and Makepeace, K. (2004): Jade (Nephrite) in British Columbia, Canada; in 37th Forum on the Geology of Industrial Minerals, B.C. Ministry of Energy and Mines, p. 287-388

Simandl, G.J., Riveros, C.P., and Schiarizza, P. (2000): Nephrite (Jade) Deposits, Mount Ogden Area, Central British Columbia; in Geological Fieldwork 1999, B.C. Ministry of Energy and Mines, p. 339-348

MINFILE database:www.empr.gov.bc.ca/Mining/Geoscience/MINFILE

Jade occurrences in BC:www.empr.gov.bc.ca/Mining/Geoscience/MINFILE/Jade

Prospecting Tips

Most nephrite deposits form lenses that 1. follow contacts between ultramafic and metasedimentary rocks.

Backtracking boulders that were dispersed 2. down-ice or downslope may help pinpoint in situ deposits.

Weathered boulders have a rough, buff, brown, 3. gray or white rind, which conceals the nephrite core.

Because nephrite is relatively hard, a hammer 4. blow to a boulder leaves little or no mark.

Rodingites, rocks rich in calc-silicate minerals 5. formed by alteration of mafic rocks near serpentized ultramafics, may indicate geological conditions favourable for nephrite.

“B.C.’s Provincial Gemstone”

The 17 ton “Magnificent Boulder” is unearthed in the Dease Lake area.

The largest producer of jade in B.C. is Cassiar Jade Contracting Ltd.

*Photos courtsey of Cassiar Jade Contracting Ltd.

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Where to Buy Bulk Jade for Carving

www.cassiarjadecontracting.comwww.jademine.com

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What is Jade?Jade is a commercial term for green, white, black, or yellow-brown jadeite and nephrite. Jadeitite is a rock that consists of the mineral jadeite (a sodium-rich, high pressure pyroxene), whereas nephrite consists of amphibole minerals (tremolite-actinolite) in which prismatic to needle-like crystals are arranged in randomly oriented bundles. All of the known jade deposits in B.C. are nephrite.

Kilometres100 200

N

Past Producer

Producer

Prospect

Showing

Blueschist

Regional Faults

Bridge River, Cache Creek& Slide Mountain Geological Terranes

Cry and Dease Lake Area

Mount Ogden Area

Southern B.C.

Cry and DeaseLake Area

Mount OgdenArea

SouthernB.C.

40 km

20 km

50 km

Pinchi Lake

Jennings River

Bridge River

Updated: July, 2012

Ultramafic (Serpentinite) Rocks

Geology and OriginNephrite is documented at over fifty sites in British Columbia’s MINFILE database. It is an alteration product of ultramafic (high magnesium and iron, relatively low silica content) rock that is commonly called sepentinite. This alteration reflects the action of heated fluids transferring elements between ultramafic and metadsedimentary or felsic igneous rocks.

Nephrite is found in the Cache Creek, Bridge River, and Slide Mountain geological terranes, which are largely of oceanic affinity. Regional faults in these terranes may indicate where ultramafic rocks are exposed.

In outcrop, nephrite typically forms lenses near contacts between ultramafic and metasedimentary or igneous rocks. Loose nephrite in boulder fields, talus, and placers also form commercial deposits.

Formed under very high pressures and modest temperatures, blueschist or eclogite-grade metamorphic rocks may point to a jadeite-forming environment. Such rocks are found in the Bridge River, Pinchi Lake, Dease Lake, and Jennings River areas.

Jade occurrences are documented in the B.C. Geological Survey Branch’s MINFILE database, which is available on the Ministry’s website at:www.empr.gov.bc.ca/Mining/Geoscience/MINFILE/Jade